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Full catalog/VJ109GA
VJ109GA·v002·dataset

True surface color (NOAA-20, daily, 500 m to 1 km)

VIIRS/JPSS1 Surface Reflectance Daily L2G Global 1km and 500m SIN Grid V002
land NASA LPCLOUD Level 2G active HDF-EOS5
In plain English

What it measures. Estimates of the true color and brightness of the land surface across twelve wavelength bands, after removing the haze and distortion added by the atmosphere. It also includes viewing angles and quality details.

How it's made. Produced daily from the VIIRS instrument on the NOAA-20 satellite, correcting raw top-of-atmosphere readings for gases and airborne particles, and resampled to 500 m and 1 km grids.

How & where you'd use it. A core input for many other VIIRS land products; on its own it supports mapping land cover, vegetation, and surface changes with the atmosphere's effects stripped out.

What's measured

LAND SURFACE › SURFACE RADIATIVE PROPERTIES › REFLECTANCE

Coverage & cadence

  • Time span2018-01-01 → ongoing
  • Measured byNOAA-20 (VIIRS)
  • Processing levelLevel 2G
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS5
  • StatusACTIVE

What you can do with it

  • Track deforestation, fire scars and land-cover change
  • Monitor crop and vegetation health (NDVI/EVI)
  • Map how built-up vs. green an area is over time
Official description

The Visible Infrared Imaging Radiometer Suite (VIIRS) daily surface reflectance (VJ109GA) Version 2 product provides an estimate of land surface reflectance from the NOAA-20 VIIRS sensor. Data are provided for three imagery bands (I1-I3) at nominal 500 meter resolution (~463 meter) and nine moderate resolution bands (M1-M5, M7, M8, M10, M11) at nominal 1 kilometer (~926 meter) resolution. The 500 meter and 1 kilometer datasets are derived through resampling the native 375 meter and 750 meter VIIRS resolutions, respectively, in the Level 2 input product. These bands are corrected for atmospheric conditions such as the effects of molecular gases, including ozone and water vapor, and for the effects of atmospheric aerosols. The inputs to the surface reflectance algorithm are top-of-atmosphere reflectance for the VIIRS visible bands, the VIIRS cloud mask and aerosol product, aerosol optical thickness and atmospheric data obtained from the NOAA National Centers for Environmental Prediction (NCEP) reanalysis system. Along with the twelve reflectance bands are reflectance band quality, sensor azimuth angle, solar azimuth angle, sensor zenith angle, solar zenith angle, and observations layers. The reflectance layers from the VJ109GA data product are used as input data for many of the VIIRS land products. Known Issues * For complete information about known issues please refer to the [MODIS/VIIRS Land Quality Assessment website](https://landweb.modaps.eosdis.nasa.gov/knownissue?sensor=VIIRS) and in Section 4.0 of the User Guide.

Get the data

vj109ga_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VJ109GA",
    version="002",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from LPCLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.